The production of reactive oxygen species (ROS) by neutrophils has a vital role in defence against a range of infectious agents, and is driven by the assembly of a multi-protein complex containing a minimal core of five proteins: the two membrane-bound subunits of cytochrome b(558) (gp91(phox) and p22(phox)) and three soluble factors (GTP-Rac, p47(phox) and p67(phox) (refs 1, 2). This minimal complex can reconstitute ROS formation in vitro in the presence of non-physiological amphiphiles such as SDS. p40(phox) has subsequently been discovered as a binding partner for p67(phox) (ref. 3), but its role in ROS formation is unclear. Phosphoinositide-3-OH kinases (PI(3)Ks) have been implicated in the intracellular signalling pathways coordinating ROS formation but through an unknown mechanism. We show that the addition of p40(phox) to the minimal core complex allows a lipid product of PI(3)Ks, phosphatidylinositol 3-phosphate (PtdIns(3)P), to stimulate specifically the formation of ROS. This effect was mediated by binding of PtdIns(3)P to the PX domain of p40(phox). These results offer new insights into the roles for PI(3)Ks and p40(phox) in ROS formation and define a cellular ligand for the orphan PX domain.
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http://dx.doi.org/10.1038/35083076 | DOI Listing |
Background: Plant senescence is a genetically controlled process that results in the programmed death of plant cells, organs, or the entire plant. This process is essential for nutrient recycling and supports the production of plant offspring. Environmental stresses such as drought and heat can hasten senescence, reducing photosynthetic efficiency and significantly affecting crop quality and yield.
View Article and Find Full Text PDFArterioscler Thromb Vasc Biol
January 2025
Department of Cardiovascular Medicine, The University of Tokyo, Bunkyo-ku, Japan. (H. Yagi, H.A., Q.L., A.S.-K., M.U., H.K., R.M., A.S., S.O., H.T., Norifumi Takeda, I.K.).
Background: Marfan syndrome (MFS) is an inherited disorder caused by mutations in the gene encoding fibrillin-1, a matrix component of extracellular microfibrils. The main cause of morbidity and mortality in MFS is thoracic aortic aneurysm and dissection, but the underlying mechanisms remain undetermined.
Methods: To elucidate the role of endothelial XOR (xanthine oxidoreductase)-derived reactive oxygen species in aortic aneurysm progression, we inhibited in vivo function of XOR either by endothelial cell (EC)-specific disruption of the gene or by systemic administration of an XOR inhibitor febuxostat in MFS mice harboring the missense mutation p.
J Nanobiotechnology
January 2025
Department of Orthopedic Surgery, Fujian Medical University Union Hospital, Fuzhou, 350001, China.
Overproduction of reactive oxygen species (ROS), elevated synovial inflammation, synovial hyperplasia and fibrosis are the main characteristic of microenvironment in rheumatoid arthritis (RA). Macrophages and fibroblast-like synoviocytes (FLSs) play crucial roles in the progression of RA. Hence, synergistic combination of ROS scavenging, macrophage polarization from pro-inflammatory M1 phenotype towards M2 anti-inflammatory phenotype, and restoring homeostasis of FLSs will provide a promising therapeutic strategy for RA.
View Article and Find Full Text PDFJ Lipid Res
January 2025
Physiology and Pathophysiology of Cells and Membranes, Medical School OWL, Bielefeld University, Bielefeld, Germany. Electronic address:
The environmental pollutant cadmium (Cd) poses a threat to human health through consumption of contaminated foodstuffs culminating in chronic nephrotoxicity. Mitochondrial dysfunction and excessive reactive oxygen species (ROS) are key to Cd cellular toxicity. Cd-lipid interactions have been less considered.
View Article and Find Full Text PDFJ Ethnopharmacol
January 2025
Chongqing Key Laboratory of New Drug Screening from Traditional Chinese Medicine, Integrative Science Center of Germplasm Creation in Western China (Chongqing) Science City & Southwest University, SWU-TAAHC Medicinal Plant Joint R&D Centre, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, P.R. China. Electronic address:
Ethnopharmacological Relevance: The roots of Oxybaphus himalaicus Edgew. is a traditional Tibetan herbal medicine with kidney reinforcing and tonifying effects, which is commonly applied to treat nephritis. Boeravinone C has been identified as one of the primary constituents of O.
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